1. Field of the Invention
This invention relates to a circuit arrangement for a dc to dc converter current supply having at least one switching transistor and one transformer, and more particularly to such a circuit arrangement in which the primary winding of the transformer is connected in the collector circuit of the transistor and the secondary winding provides at least one stabilized dc voltage by way of rectifiers, and wherein the switching transistor is actuated and blocked by way of a control component in dependence upon load.
2. Description of the Prior Art
Current supply devices with chopper transistors have various advantages in comparison to current supply devices having low frequency mains supply transformers. The chopper transistor configurations are small and light and generally possess a high degree of efficiency. A fundamental problem which arises in these circuits consist in that, in practice, substantial power loss can occur in the switching transistor as the applied current and voltage do not suddenly change for the transistor. Thus, current will flow through the transistor while the latter is prematurely or maintained connected to a voltage.
In known dc to dc converters, a control component is provided which serves to control the transistor and which constantly compares the secondary voltage with a theoretical value and, via an adjusting element, emits corresponding switching pulses to the base of the switching transistor. Voltage regulators of this type are relatively expensive and, furthermore, are unable to react to the actual conditions in the transistor so that the switching losses may be excessively high. A large portion of the losses lies in the switch-off edge for the transistor.